来流Mach数连续变化下的激波串运动特性

为了研究入射激波变化的隔离段内激波串的运动特性，设计并搭建了直连式变Mach数实验系统，捕捉了相同来流Mach数变化速率、不同背压变化速率下激波串的运动行为，揭示了入射激波与背压同时变化对激波串运动的影响机理。入射激波与背压同时变化时，共有3个方面的因素会影响激波串整体的上下游运动趋势，其一，Mach数变化，Mach数增大导致激波串向下游运动，该影响随Mach数增大逐渐减弱；其二，背景波系移动，背景激波反射点靠近激波串前缘时，可能引起激波串的突跳；其三，背压压比变化，背压压比增大时激波串向上游运动，该影响随背压压比增大逐渐增强。三方面因素共同作用下激波串表现出复杂的运动。 

Movement Characteristics of Shock Train Under Continuous Change of Incoming Mach Number

In order to study the movement characteristics of shock train with the variation of incident shock, a direct-connect wind tunnel experimental system with variable incoming Mach number was built. The movement behavior of shock train under the same change rate of incoming Mach number and different change rates of backpressure was captured. The influence mechanism of the synchronous change of incident shock and backpressure on the shock train movement was revealed. When the incident shock and the backpressure change at the same time, there are three factors that affect the overall upstream and downstream movement trend of the shock train. The first is the change of incoming Mach number. The increase of incoming Mach number leads to the downstream movement of the shock train, and the influence gradually weakens with the increase of the incoming Mach number. The second is the movement of the background waves. When the impingement point of the background wave approaches the shock train leading edge, the sudden jump of the shock train can be caused. The third is the change of backpressure ratio. When the backpressure ratio increases, the shock train moves upstream, and the influence gradually increases with the enhancement of backpressure ratio. The shock train exhibits complex movements under the coupling effect of the three factors.